The invention relates to improvements in apparatus for applying one or more films or layers of coating material to running substrates of paper, textile, metallic foil, plastic foil or other strip- or web-shaped products. More particularly, the invention relates to improvements in apparatus of the type disclosed in U.S. Pat. No. 4,886,564 which discloses apparatus for the application of a plurality of more or less solidified films or layers of coating material (such as an adhesive, a coloring agent or an impregnating substance) to one side of a running substrate so that successively applied layers or films overlie each other.
The patented apparatus employs several endless carriers which transport films of originally liquefied coating material toward a series of stations where the coating material is transferred onto spaced-apart portions of the substrate or onto the previously applied film or films of coating material. The coating material often contains solvents which must be expelled from the coating material in a predictable manner in order to prevent the development of blisters and/or other irregularities which could affect the appearance and/or quality of the finished product, e.g., adhesive tape, band aid or the like.